1 Technical Field
The present invention relates generally to an improved structure of a rear portion of an automotive vehicle body.
2 Background Art
Japanese Patent First Publication No. 10-129533 shows a rear body of a vehicle in which a reinforcement member is installed diagonally to connect an end portion of each rear side member to an end portion of a rear cross member across a joint of them to increase the torsional rigidity of the rear portion of the vehicle body, thereby distributing the energy of an impact force upon occurrence of a rear-end collision of the vehicle to the rear side members, the rear cross member, and rear wheel houses so as to define an impact absorbing structural portion occupying a portion of the vehicle body in front of the reinforcement members and a vehicle body deformable portion occupying the remaining portion of the vehicle body on the rear side of the reinforcement members.
Specifically, the above vehicle body structure is designed to absorb the energy of an impact force produced by a rear-end collision of the vehicle through structural members such as the rear side members arranged at a lower portion of the vehicle body and thus encounters the drawback in that it is very difficult to distribute the energy of the impact force up to an upper portion of the vehicle body effectively. Further, since the lower portion of the vehicle body absorbs the energy of the impact force as a whole, the need may arise for reconditioning or replacing the whole rear portion of the vehicle body.
It is an object of the present invention to provide an improved structure of a rear portion of an automotive vehicle body which is designed to absorb the energy of impact produced by a vehicle collision through both an upper and a lower portion of the vehicle body.
According to one aspect of the invention, there is provided a rear body of an automotive vehicle which comprises: a front body structural element made of a cast defining a front portion of the rear body; and a rear body structural element made of a cast. The rear body structural element is joined to said front body structural element to define a rear portion of the rear body and has a rigidity smaller than that of the front body structural element.